JPH0252214B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a white smoke concentration measuring device, and particularly to a white smoke concentration measuring device suitable for measuring white smoke concentration in exhaust gas.

[Background of the invention]

Various smoke meters have been proposed as devices for measuring black smoke components in exhaust gas. These smoke meters were developed for measuring black smoke, and when these smoke meters are used for measuring white smoke, the following problems occur.

In the case of a smoke meter that measures black smoke concentration from exhaust gas that is not diluted by air, part or all of the exhaust gas is introduced into a cell, and the transmittance of light irradiated into the cell is used to measure the concentration of black smoke in the exhaust gas. The apparatus is configured to measure black smoke concentration. For this reason, when using this type of smoke meter to measure the white smoke concentration in exhaust gas, the exhaust gas is not diluted and cooled by the atmosphere, so white smoke is not generated sufficiently, and the exhaust gas temperature and measurement cell It is not possible to accurately measure the white smoke concentration because it is affected by the length of the introduction line, etc.

In addition, in the case of a type of smoke meter that is diluted by the atmosphere, the entire amount of exhaust gas is injected into the atmosphere introduction passage or into the atmosphere, and light is irradiated into the air passage or the exit of the exhaust pipe. It is configured to measure the black smoke concentration in exhaust gas from the light transmittance. When measuring the white smoke concentration with this type of smoke meter, the amount of white smoke generated varies depending on the ambient temperature at the outlet, and the dilution rate varies depending on the engine displacement. Even if the white smoke concentration is , the reading of the smoke meter changes, making it impossible to accurately measure the white smoke concentration.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide a white smoke concentration measuring device that can accurately measure the concentration of white smoke in exhaust gas.

[Summary of the invention]

The present invention provides an exhaust gas introduction path that heats the exhaust gas introduced from the exhaust gas introduction port to a predetermined temperature and guides it to the exhaust gas outlet side, and a black smoke component of the exhaust gas inserted into the exhaust gas introduction path. A filter to filter,
A flow rate adjustment device that maintains the flow rate of exhaust gas discharged from the exhaust gas outlet of the exhaust gas introduction path at a predetermined amount, and a flow rate adjustment device that maintains the flow rate of exhaust gas discharged from the exhaust gas discharge port at a predetermined amount. a white smoke generator that discharges generated white smoke from an exhaust port;
The above object is achieved by a white smoke concentration measuring device equipped with a white smoke concentration detector that irradiates light into a white smoke generating device and detects the white smoke concentration from the transmittance or reflectance of this light. It is characterized by what it did.

[Embodiments of the invention]

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

The accompanying drawings illustrate the construction of a preferred embodiment of the invention.

In this embodiment, as shown in the attached drawings, the main body of the white smoke concentration measuring device is inserted into a measurement chamber 10 whose room temperature is maintained below 0°C, and the exhaust gas introduction passage 12 is connected to the engine 14. It is connected to the exhaust pipe 16.

The exhaust gas introduction path 12 is formed as a heating line 18, and the exhaust gas introduced from the exhaust gas introduction port 20 is heated to a predetermined temperature, such as 200° C., at which white smoke components do not adsorb to the exhaust gas and white smoke condensation does not occur. It is configured to heat the gas to a temperature of .degree. C. and guide it toward the exhaust gas outlet 22 side. Further, in this embodiment, a bypass path 24 branched from the exhaust gas introduction path 12 is provided. The exhaust gas introduction path 12 is not only heated entirely by a heating device such as a heater, but also is insulated and kept warm so as not to be affected by indoor cooling.

Further, a filter chamber 26 is formed in the middle of the exhaust gas introduction path 12, and this filter chamber 26
A heated filter 28 for filtering black smoke components in the exhaust gas is inserted inside. The filter 28 is
The filter element is surrounded by heating wires, and is heated by the heat generated by the heating wires. That is, the heating type filter 28 is used to heat the exhaust gas introduced into the heating line 18 and gasify white smoke components in the exhaust gas. Therefore, the white smoke component in the exhaust gas passes through the filter 28, but the black smoke component is filtered by the filter 28. The exhaust gas filtered by the filter 28 is sent to the exhaust gas outlet 22 side by a heating pump 30 downstream of the filter 28 .

In order to maintain the flow rate of exhaust gas discharged from the exhaust gas outlet 22 at a predetermined amount, in this embodiment, a flow rate regulating valve is provided in the exhaust gas introduction path between the heating pump 30 and the exhaust gas outlet 22. 32 is disposed, and a heated pressure regulating valve 34 is disposed in the middle of the bypass line 24. That is, in order to maintain a constant pressure in the exhaust gas introduction path between the pump 30 and the flow rate adjustment valve 32 so that a constant amount of exhaust gas is always fed from the flow rate adjustment valve 32 to the exhaust gas outlet 22 side. Adjustment is made by heating type pressure regulating valve 34.
It is carried out by. When the pressure in the pipeline between the flow rate regulating valve 32 and the pump 30 exceeds a certain pressure, excess exhaust gas is discharged via the pressure regulating valve 34 and the bypass pipe 24, and the exhaust gas is discharged from the exhaust gas outlet 22.
A predetermined flow rate of exhaust gas is always discharged from the exhaust gas. That is, the pump 30, the flow rate adjustment valve 32, the pressure adjustment valve 3
4. Exhaust gas outlet 2 by bypass pipe 24
A flow rate adjustment device is configured to maintain the flow rate of exhaust gas discharged from 2 at a constant amount. The exhaust gas outlet 22, whose pressure is indicated by a pressure gauge 35 in accordance with the opening degree of the pressure regulating valve 34, is inserted into the white smoke generator 40.

The white smoke generator 40 is separated into an air introduction chamber 46 and a fluid mixing chamber 48 with an orifice 44 as a boundary, and the air introduction port of the air introduction chamber 46 has a measuring chamber 1
A filter 50 is installed to filter out impurities contained in the air inside the chamber 48, and a pump 52 is installed on the downstream side of the fluid mixing chamber 48. Further, the fluid mixing chamber 48 of the white smoke generating device 40 includes a light projecting section 56 that irradiates light, and a light projecting section 56 that receives the light from the light projecting section 56. A light receiving section 58 is provided to detect the white smoke concentration in the measurement chamber 1.
The signal is supplied to a recorder 60 installed outside the station. Further, an air introduction pipe 62 for pressurizing the air curtain is provided in the light projecting section 56 and the light receiving section 58. When the pump 52 operates, the cooled air in the measurement chamber 10 is introduced into the air introduction chamber 46 through the filter 50. This air is in orifice 4
A predetermined amount of exhaust gas is sucked into the fluid mixing chamber 48 through the exhaust gas discharge port 64 and mixed in the fluid mixing chamber 48 with a predetermined amount of exhaust gas discharged from the exhaust gas discharge port 22. The mixed fluid is discharged from the fluid discharge port 64. do. When the heated exhaust gas and the cooled air mix within the fluid mixing chamber 48, white smoke is generated within the fluid mixing chamber 48. Each time this white smoke is discharged to the fluid outlet 64 side, the white smoke concentration in the fluid mixing chamber 48 is sequentially recorded in the recorder 60 based on the detection output of the light receiving section 58.

In the above configuration, when exhaust gas is discharged from the engine 14, a part of the exhaust gas in the exhaust pipe 16 is introduced into the exhaust gas introduction passage 12, heated to a temperature higher than the exhaust temperature, and flows to the exhaust gas outlet 22 side. guided in sequence. Then, a predetermined amount of exhaust gas from which black smoke components in the exhaust gas have been filtered by a filter 28 provided in the middle of the exhaust gas introduction path 12 is transferred to the fluid mixing chamber 4.
At the same time, a certain amount of cooled air is introduced into the fluid mixing chamber 48, and white smoke is generated in the fluid mixing chamber 48 by mixing the heated exhaust gas and the cooled air. . When the white smoke generated in the fluid mixing chamber 48 is sequentially discharged from the fluid outlet 64 by the operation of the pump 52, the white smoke in the fluid mixing chamber 48 is caused by the light irradiated into the fluid mixing chamber 48. The density is sequentially recorded on the recorder 60 according to the detection output of the light receiving section 58.

In this way, in this embodiment, the exhaust gas is heated to a temperature higher than the exhaust temperature, the black smoke components in the heated exhaust gas are filtered, and a predetermined amount of this exhaust gas is discharged, and a predetermined amount of cooled air is mixed with the exhaust gas. Since they are mixed, the concentration of white smoke made up of HC components can be measured with high precision without being affected by engine displacement or exhaust temperature. That is,
In this embodiment, the white smoke concentration can be measured under the same conditions as when actually being released into the atmosphere, and moreover, the white smoke concentration can be measured continuously.

In addition, in this embodiment, from the air introduction pipe 62 to the light irradiation surface of the light projecting section 56 and the light receiving surface of the light receiving section 58,
Since pressurized air is supplied, it is possible to prevent an error from occurring in the measured value of the white smoke concentration due to dirt on the light projecting section 56 and the light receiving section 58.

〔Effect of the invention〕

As explained above, according to the present invention, the introduced exhaust gas is heated to a temperature higher than the exhaust temperature, the black smoke component in the exhaust gas is filtered, and a certain amount of the exhaust gas from which the black smoke component has been filtered is discharged. However, since the exhaust gas is mixed with a certain amount of cooled air to generate white smoke, there is an excellent effect that the white smoke concentration in the exhaust gas can be measured with high accuracy.

[Brief explanation of the drawing]

The accompanying drawings are configuration diagrams showing one embodiment of the present invention. 10...Measurement chamber, 12...Exhaust gas introduction path, 16...
Exhaust pipe, 18...Heating line, 28...Filter, 3
0... Heating type pump, 32... Flow rate adjustment valve, 34... Pressure regulation valve, 40... White smoke generator, 52... Pump,
56... Light projecting section, 58... Light receiving section.

Claims (1)

[Claims] 1 An exhaust gas introduction path that heats the exhaust gas introduced from the exhaust gas introduction port to a predetermined temperature and guides it to the exhaust gas discharge port side, and a filter inserted into the exhaust gas introduction path that filters black smoke components of the exhaust gas. , a flow rate adjustment device that maintains the flow rate of exhaust gas discharged from the exhaust gas discharge port of the exhaust gas introduction path at a predetermined amount, and a flow rate adjustment device that maintains the flow rate of exhaust gas discharged from the exhaust gas discharge port at a predetermined amount; a white smoke generator that discharges white smoke generated by mixing from an exhaust port; a white smoke concentration detector that irradiates light into the white smoke generator and detects the white smoke concentration from the transmittance or reflectance of the light; A white smoke concentration measuring device characterized by: